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<PRE>&lt;dy 090920 ok&gt;
<A HREF="CAD_using_en.htm">See operating CAD ..</A>



CAD-functions for modifying geometry




 CUT, Trim
 Intersect, intersection curves (INT)
 Transform (move, rotate) (TRA)
 Project
 Mirror 



<p><a name="F0"></a></p>
<h2>CUT (trim) obj          CUT</h2>
 Trim / limit linear elements (lines, curves).
   (Separate with one or two cutting elements).

 Caution: currently only for curves, not yet for surfaces/solids and CCVs.

<b>CUT Obj CuttingElement (CuttingElement2) (Variant) (REVerse)</b>

<b>Obj:</b> this element will be changed (trimmed).
    If it is already trimmed, also its parent-object will be displayed
    in the selection-list.

<b>Cutting element:</b> the object will be separated with this element 
    one (optionally two) elements, e.g. points.
    For curves, parameter values (0-1) can be used.
    Two cutting elements: result is the mid-part.
    
<b>Variant:</b> which of the resulting elements will be retained
    Other/s will be discarded 
    Change with the Page Up/Page Down keys
    Default or “1” saves the first resulting object 

<b>REVerse:</b> Reverse the direction of the resulting curve.

<img src="doc_L_cut__.jpg" alt="versions">

 Example:
 L20 = P(-60 30 0) P(20 70 0) 
 C20 = P(-14 40 0) VAL(32) DZ
 S20 = CUT C20 L20 L20
 # Circle C20 is limited at both ends (trimmed).

 # Parameter values as cutting element:
 S21 = CUT S20 0.33 0.66



<p><a name="F1"></a></p>
<h2>INT (intersect) obj     INT</h2>
Create intersection points / intersection curves.

<b>resulting_object = INT Obj1 Obj2 [version] [POL]</b>

 Obj1: object 1
    Curve or surface. Continue with Tab-key

 Obj1: object 2
    Curve or surface
    For curves, parameter values (0-1) can be used.
         
 Version: Define which element of the result is to be saved.
    Other/s are discarded.
    Select using the PageUp/PageDown keys.
    Default or &quot;1&quot;: Saves the first result object (point or curve)
     &quot;2&quot; would select the second one ..

 POL: Only for curves as a result
    output is polygon or spline (default is spline) 

 Example:
 P20 = P(-62.5 -63.7 0)
 S20 = CCV P20 P(-20 -70) P(-40 -15) P20
 A20 = S20
 #
 P21 = P(-60 -110 20)
 P22 = P(S20 MOD (2) 1)
 S21 = POL P21 P20 P22 P21
 A21 = S21
 #
 R20 = X(-35)
 #
 # A group of Areas:
 S22 = INT U(A20 A21) R20 POL

# point from intersection line x surface:
P1=INT L1 A1

# curve from intersection curve X surface:
# (curve: circle, ellipsis, B-Spline) not yet implemented

# curve from intersection surface x surface:
S1=INT A1 A2



<p><a name="F2"></a></p>
<h2>TRAnslate obj (VC)      TRA</h2>
 Translate an object

 Result = Object TRA Obj_to_move vector [length]
   TRA Obj_to_move: this object is moved
   <a href="CAD_Base_en.htm#D">Vector</a>
   length       vectorlength (optional)
   replace-duplicat   if parentobject should be kept or hidden; default = keep.
                      press Page-down to keep ("REPL").

 A new, translated object (a copy) will be created.
 Permanent translation of the selected object: use "Group/move objects of group"


# Objects to move a vector (REV: opposite direction). 
# Obj = vec TRA obj/traVC [REV] 
P20 = P(100,0,0) 
P21 = TRA P20 D(0 0 100) 
 
# "TRafo transl"  (define Transformation)
T20 = D(10 10 10) 
# "TRAnslate obj (VC)"  and keep parent
P22 = TRA P21 T20
# TraVC (T20 in the example): see Transformation 
# replace parent
P23=TRA P22 D(0 0 100) REPL




<p><a name="F3"></a></p>
<h2>TRAnslate obj (PLN)     TRA</h2>
 Move an object to a different reference system.
   Each layer can be used as a reference system.

 Result object = TRA object reference system [REV]
   Reference System
   REV: Move an object from a reference system back into the main location.

 Example:
 R20 = P(100 100 25) D (-1 0 2)
 L20 = P(100 100 25) P (100 120 25)
 # Move line L20 to the Refsys R20
 L21 = TRA L20 R20
 # Move a line back into the main location.
 L22 = TRA L21 R20 REV



<p><a name="F4"></a></p>
<h2>TRAnsform obj (Tra)     TRA</h2>
 Transformation of objects (move, rotate).
 The transformation must be defined previously!

 Result object = TRA object transformation
   Transformation: Select example using the PageUp/PageDown keys 

 Translation:
 P20 = P(100 0 0)
 Translation # Z in the direction of 100 mm
 T20 = DZ VAL(100)
 P21 = TRA P20 T20

 Rotation:
 P20 = P(100 0 0)
 # Define a 30-Grad-Rotation to line L20
 L20 = P(50 0 0) P(50 0 10)
 T20 = ROT L20 ANG(90)
 # P20 rotate
 P21 = TRA P20 T20



<p><a name="F5"></a></p>
  <h2>reverse curve      REV</h2>
Reverse direction of curve.
The resulting curve looks identical.



<p><a name="F6"></a></p>
<h2>Project obj        PRJ</h2>
Project points or linear elements (lines, circles, curves) onto 
  an other linear element or on a surface.

Resulting_object = PRJ object targetObject [direction] [solutionNr]

object:          project this object -
targetObject:    - onto this object.
direction:       projection-direction, a vector; none: normal to targetObject.
solutionNr:      1-n, PgUp/PgDown keys.


 Example:
 P21=PRJ P20 R20
 # Point P20 will be projected on the plane R20; direction is perpendicular.

 S20 = PRJ S20 R20 D20
 # Curve S20 will be projected in direction of D20 on the plane R20 



<p><a name="F7"></a></p>
  <h2>Mirror about line       MIR</h2>
Reflect objects across a line
  Currently, only for linear elements, plane, not surfaces.

resulting object = MIR object line


Beispiel:
S20=MIR S20 L20
# Curve S20 is mirrored across line L20



<p><a name="F8"></a></p>
<h2>Mirror obj (Plane)      MIR</h2>
 Reflect objects across a plane
   Currently, only for linear elements, not surfaces

 Result object = MIR object plane

 Example:
 S20 = MIR S20 R20
 # Curve S20 is mirrored across plane R20



<p><a name="F9"></a></p>
<h2>ISOparametric Curve from Surf         ISO</h2>
 Extracts an isoparametric curve from a surface.
  Currently only B-Spline surface. Entering point or parameter value has not yet been implemented 

 Input:
 Surface
 Parameter value (0-1)
 Default: lengthwise Direction; &quot;CX&quot; defines lateral direction.
 (Modifier CX = across; Default = along)

 S = parameter surf ISO/point (direction U/V)

 Example:
 # Cross-section curve in the middle of the surface A20:
 S20 = ISO A20 .5 CX



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